(3-Oxo-2,3-dihydro-1H-isoindol-1-yl)acetylguanidine derivatives of the formula I
are NHE1 inhibitors and are described in PCT/EP03/05279. However, the syntheses described there lead to racemic regioisomer mixtures, which entails costly and inconvenient separation processes and reduces the yield of the desired compound. Hitherto, it has only been possible to obtain the isomers by a costly and inconvenient chromatographic separation on chiral supports. However, the substance throughput is restricted in chromatographic separations.
There is therefore a great interest in finding regioselective preparation processes for (3-oxo-2,3-dihydro-1H-isoindol-1-yl)acetylguanidine derivatives and processes for recovering the enantiomers.